Bluetooth (BT) is a short-range wireless communication protocol, for mobile phones, computers, digital cameras, wireless headsets, speakers, keyboards, mice or other input peripherals, and similar devices. BT supports a personal area network (PAN) between a master and a plurality slaves.
For quality of transmission over BT, for example, for voice traffic, a synchronous connection-oriented (SCO) link or extended SCO (eSCO) link may be employed. To guarantee adequate bandwidth, an SCO or eSCO link reserves specific time slots as dedicated to the eSCO or SCO traffic. As a result, other wireless communication can be relegated to asynchronous “unreserved” time slots, e.g., Asynchronous Connection Oriented Channels (ACL) in a similar manner as WLAN. WLAN may be relegated to the unreserved time slots during SCO or eSCO operation, which may prevent proper operation of WLAN.
BT, however, can have power consumption higher than desired for certain low power applications. A variation, termed Bluetooth Low Energy or “BTLE” was developed, which has proved useful for many application, enabling new applications that were not practical with Classic Bluetooth technology. For example, BTLE is used in coin cell battery-operated sensors and actuators in medical, industrial, consumer, and fitness applications (also known as “Smart”) can now smoothly connect to BTLE enabled smart phones, tablets, and the like (also known as “Smart Ready”).
Conventional BTLE can be particularly useful for applications requiring episodic or periodic transfer of small amounts of data.
Many features of Classic Bluetooth technology are inherited in BTLE, such as adaptive frequency hopping (AFH) as well as part of the logical link control and adaptation protocol (L2CAP) interface, and certain security aspects such as simple pairing modes, secure authentication, and encryption.
However, BTLE did not inherit BT Synchronous Connections (SCO) or extended Synchronous Connections eSCO. This can render BTLE impractical or not preferred for certain streaming applications, for example, audio streaming. Such impracticality can result from BTLE being originally designed to carry small data packets. However, typical BTLE “on-air” is a fractional time resource, as many such devices are often kept in a “sleep” mode.
One partial solution is a “dual mode” device, switchable between Classic BT and BTLE. However, dual mode BT-BTLE devices have various shortcomings. For example, valuable chip area can be taken, and power loss can arise from supporting two technologies.
Therefore, a need remains for low power BTLE benefits with BT streaming capability.